384 RHINOCEROS. 



isolated flattened conical cusp, as in Gervais' fig. 3; PL II. of torn. ii. 

 of the ' Memoirs of the Montpellier Academy of Sciences,' but of a 

 larger size than in that figure. The posterior colline is seen to be but 

 slightly abraded by wear ; the whole of the posterior fossette and the 

 central crochet convolutions are entirely concealed by matrix. This 

 tooth appears to be nearly in the same stage of abrasion as p.m. 4 of 

 the opposite side. 



3. The penultimate premolar (p.m. 3). — The whole of the shell of 

 this tooth is present, but the outer half of the crown is completely en- 

 veloped by matrix. The anterior and posterior barrels are seen to be but 

 slightly abraded, i.e. to about the same extent as t.m. 2 ; the breadth of 

 the tooth across the anterior division is much greater than the length. 

 There is a crenulated anterior talon, but only a very obscure appearance 

 of bourrelet at the base of the anterior barrel ; none is visible behind, 

 but this part of the tooth is enveloped by matrix. The vertical furrows 

 upon the outer surface of the enamel of this and the preceding tooth 

 are but very indistinctly marked. The same observation applies to 

 p.m. 4, of the opposite side, in which the anterior vertical furrow is 

 also indistinctly marked. 



4. The last pi-emolar (jp.m. 4) on this side, as already remarked, 

 appears entirely wanting, and its position is occupied by a block of 

 matrix ; but on reversing the cranium, it is distinctly seen enclosed in 

 its alveolus, below the mass of matrix. 



5. The antepenultimate true molar (t.m. 1). — The crown of this 

 tooth is nearly perfect, althotvgh somewhat shivered. The summit is 

 almost entirely enveloped by matrix concealing the crochet and other 

 convolutions. The v ertical furrow of the anterior outer angle is broad 

 and shallow, but well jDronounced — broader than in De Christol's fig. 18 

 (see PL XVIII. fig. 3). The summits of the barrels are in the same stage 

 of wear as described of the tooth of the opposite side. The outer surface 

 of the posterior division is slightly concave and flattish. 



6. The penultimate true molar (t.m. 2). — This has its crown more 

 exposed than on the opposite side, but it has been fractured, and the 

 pieces have been imperfectly replaced. The peculiar twist of the apices 

 of the barrels has been already noticed. The anterior vertical furrow seen 

 at the outer angle of the tooth of the opposite side is also here well marked. 



7. The last true molar (t.m. 3), on the left side, is distinctly seen 

 in the state of germ, hardly emerged above the alveolar level, and em- 

 bedded in the jaw. About an inch in height of the posterior ridge is 

 exposed by the removal of the alveolar wall. The edges are quite in- 

 tact, and about an inch and a half below the level of the next preceding 

 tooth. The principal valley is completely filled up by matrix, but it is 

 visible that the crown had the sub -triangular form, which is charac- 

 teristic of the same tooth in the existing bi-corned African Rhinoceros. 



Obs. 1. — The enamel siuface in all these teeth is tinged of a bluish 

 grey, which Cortesi compares to an incipient tint of turquoise. The 

 enamel is perfectly smooth, i.e. entirely free from any superficial ru- 

 gosity, as in the tichorhine Rhinoceros, and I coidd detect upon none of 

 the teeth any indications of a coat of cement. There is certainly nothing 

 approaching the enormous coat of cement seen on the teeth of Rhi- 

 noceros hemita'chus) the enamel is not so thick as in that species, nor 

 so rugous on the surface. The ivory-core of all the teeth is highly in- 

 filtrated with iron, showing a dark amber colour; the general colour of 



